Introduction to Legacy

Welcome

In 1989 Legacy Systems, Inc. began researching improvements and new techniques in semiconductor wet processing. By 1990, Legacy developed TeflonTM Gas Diffusers for dispersion of anhydrous gases into deionized water. The result was an increase in gas absorbtion efficiency. In 1991, Legacy introduced the first Point-of-Use Generator using the Gas Diffusers. This provided a less expensive alternative to bottle-poured or drum-fed chemicals.

Legacy began to manufacture High Flow Ozone Generators in 1992. These generators replaced hydrogen peroxide in sulfuric photoresist strip applications. One to three sulfuric wafer process tanks were fed from a single ozone generator. In 1993, Legacy introduced In-Situ Chemical Generators which combined the high purity chemistries from the Point-of-Use Generators with a superior cost of ownership. Legacy received hardware patents and a patent for ColdstripTM, our chilled ozone process, in 1995. ColdstripTM eliminates the use of sulfuric acid, hydrogen peroxide, and the subsequent rinse associated with Piranha solutions.

In 1997, ColdstripTM won recognition by the United States Environmental Protection Agency, receiving the Green Chemistry Challenge Award for hazardous waste reduction, which serves to create a safer workplace. In 1998, Legacy integrated feedback concentration control technology into our ozone and chemical generation equipment. This feature allowed the process engineer to tailor the chemical concentration to his needs. The equipment was then capable of monitoring and maintaining the desired concentration set point. In 1999 and 2000, Legacy introduced ColdstripTM Generation IV and our patented solvent drying, DryZoneTM Wafer Dryer.

Legacy has strong patented technology. We are gaining recognition as an innovative company with very cost effective, environmentally-friendly products. Legacy is poised to become a major participant in the wet-process equipment market segment, as a supplier to both end users and wetstation manufacturers.

LOG-3ST

Ozone Generation System

A flexible design of Ozone Equipment permits the delivery of ozone gas streams to single or multiple use points or the delivery of single or multiple ozonated water streams to multiple use points.  The Ozone hardware is used in traditional batch wafer wetstations, batch wafer spray stations, and single wafer processing equipment to deliver ozone gas for in-situ chemical formation or liquid ozonated solutions to the process chambers.  Ozone generators with production ranges from 10g/hr to 500g/hr are configured on an as needed basis.

The systems are used to remove Photoresist, Organic Contamination removal in Prediffusion Cleans, and to Passivate Silicon Surfaces

Why we're the best!

Customer Success 

  • Process - Gate Oxide Cleaning
  • Equipment - LOG-3ST
  • Results - Yield Increase Range 1.7% - 12.2% 

Generation III

ColdStrip ™

The system utilizes only water and oxygen as raw materials.  It has the lowest cost of ownership of any wet resist strip process, saving over $300,000 per year per wetstation  when compared to a sulfuric:peroxide system.  The key process parameters are water temperature, ozone dispersion, and ozone concentration.  This photoresist stripping mechanism for Coldstrip™ doesn’t lift carbon resists off the wafers into solution, but digests and oxidizes the photoresist to soluble chemistries and gaseous carbon dioxide.  Particles due not build up in solution and redeposit on wafers as is customary with conventional sulfuric acid mixtures or solvent strippers